Grinding machine



Dec. 19, 1939. A. R. JOHNSON GRINDING MACHINE Fild March 51, 1938 2 Sheets-Sheet 1 ATTORNEYS A. R. JOHNSON GRINDING MACHINE Dec. 19, 1939.

2 Sheets-Sheet 2 Filed March 31, 1938 ATTO RN EYS that the cutlery may Patented Dec. 19, 1939 UNITED STATES PATENT OFFICE 1 Claim.

pensive, portable power driven device of this character whereby a person with ease may properly sharpen cutlery through the use of an endless belt-like grinder and a grinding wheel, the device being so constructed that the grinding operation may be carried on without interference from improperly positioned parts and with economy, the bearings, power means and other parts of the device being protected from the grindings and adjustable rests being provided so be properly suppported relative to the grinder during the sharpening operation.

With these and other objects in View, this invention consists in certain novel features of construction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of my invention, reference is to be had to the following description and accompanying drawings, in which Figure 1 is a side elevation, partly in section, illustrating a grinding machine constructed in accordance with my invention.

Figure 2 is an end elevation, partly in section, illustrating the same.

Figure 3 is a transverse sectional view taken on line 3-3 of Figure 1.

Figure 4 is a fragmentary top plan view illustrating the device.

Figure 5 is a disrupted front elevation showing a tightener used in conjunction with the endless belt type grinder.

Figure 6 is a perspective view illustrating one of the members of a rest.

Figure 7 is a detail sectional view showing the mounting of said member in a standard of the device.

Figure 8 is a side elevation illustrating a modification of my invention.

Figure 9 is a fragmentary perspective view of a tool rest showing an adjustable support thereon.

Referring in detail to the drawings, the numeral I indicates a base on which is mounted an electric motor 2 equipped with a belt pulley 3 capable of adjustment endwise of the power shaft 4 of the electric motor. The electric motor is located adjacent one end of the base and adjacent the opposite end of the base are pedestals or standards 5 having journals 6 to rotatably support a shaft 1 on which is secured a plurality of closely related belt pulleys 8 of different sizes. An endless belt 9 is employed for connecting the pulley 3 to any one of the pulleys 8 so that the shaft I may be driven at different rates of speed by the electric motor. It is preferable that the pulleys 8 be of the peripheral grooved type.

One end of the shaft I has secured thereon a grinding wheel 9 having associated therewith a rest II! on which cutlery may be positioned to be brought in contact with the periphery of the grinding wheel. The rest I is carried by a support II mounted on the standards or pedestals and which includes separable sections adjustably connected by a bolt I2 which will permit the rest II] to be adjusted towards and from the grinding wheel 9 and also to be adjusted towards and from either peripheral edge of the grinding wheel. The rest IIJ also may be adjusted verv tically and held in the vertical adjusted position by a set screw II. The journals 6 have suitable lubricating cups to maintain the journals and the shaft thoroughly lubricated at all times.

The other end of the shaft I has mounted thereon a pulley I3 over which'is trained an end less belt type grinding element I4, the latter also being trained over a pulley I5 journaled on a standard It carried by the base I. The endless grinding element I4 may be constructed of any material suitable for the purpose and is engaged by a tightener I'I mounted on the base I. The tightener I'I includes a bracket I8 secured on the base and having a vertically arranged portion to which a member I9 is adjustably secured. The member I9 has a flanged pulley journaled thereon contacting with the lower run of the endless grinding element I4. Through the adjustment of the member I9 on the bracket I8 the endless grinding element may have the slack therein increased and decreased as described.

The standard I6 has a cutlery rest ZI adjustably mounted thereon. The rest ZI includes a table 22, a vertical member 23 secured to said table and adjustably mounted in a head 24 of a member 25. The member 25 is adjustably mounted in the standard It. The members 23 and 25 being adjustable relative to each other permits the table 22 to be adjusted vertically and. the member 25 being adjustable on the standard I6 permits the table 22 to be adjusted towards and from the pulley I5. The table 22 is so positioned that a razor, knife or the like supported thereon may be brought in contact with the grinding element I4 as the upper run leaves the pulley I5. This arrangement permits the operator to efficiently and accurately grind the knife or razor.

The table 22 has slidably mounted thereon a support 2! and which may be adjusted on said table through the rotation of a finger piece 22' forming an integral part of a screw threaded stem 23' having threaded engagement with a screw threaded opening of an ear 24' formed on the support 2|. The support 2| may be adjusted toward and from the endless grinding element l4 when the latter passes over the pulley I5. The purposev of the support 2| isto maintain a razor at a proper inclination to the endless grinding element 14 where the latter leaves the pulley l5 to assure efficient grinding of the cutting edge of the razor, the non-cutting edge lying on the rest 2!. To grind a razor properly, the grinding operation is from the non-cutting edge toward the cutting edge and throughout the length and width of the razor. To accomplish this the rest 2! is lowered so that when the razor is positioned with the non-cutting edge thereof on the support 2! the endless grinding element 14 as it leaves the pulley I5 will be contacting the razor adjacent to the non-cutting edge and as the grinding operation continues the support 2| is moved toward the element l4 thus bringing about the grinding of the razor towards the cutting edge. The diameter of the pulley i5 must be such that it will present a proper curvature to the endless grinding element it as it leaves said pulley E5 to fit in the hollow face of the razor between the cutting edge and the non-cutting edge. By gradually grinding the razor from the non-cutting edge toward the cutting edge brings about a proper sharpening of the cutting edge so that very little honing is required of the cutting edge in order that the cutting edge become extremely keen or sharp. The rest 2| being of the construction described will assure against the slipping of the razor during the grinding operation and consequently obviate possibility of marring or nicking the cutting edge. The member 25 being provided with a fiat face engaged by the set bolt 28' will prevent the member 25 from wobbling in its support, consequently maintaining the table 22 level and in proper position with respect to the endless cutting element as it leaves the pulley 55. It will also be noted that the edge of the table 22 adjacent the pulley i5 is cut away to permit straddling of the pulley and the endless grinding element by the table and which will permit the support 2 I to be adjusted as close to the pulley l5 as desired. Through this arrangement of table 22 the support 2i has a comparatively wide range of adjustment toward and from the pulley i5 and the endless grinding element as it leaves said pulley I5 so that razors of various widths can be accommodated and properly ground.

Shears, scissors or the like are ground on the grinding wheel, 9, they being supported by the rest. It during the grinding operation.

A guard 26 is mounted on the pedestal of the electric motor and protects the latter from grindings from the grinding elements. A guard Z'lis carried by the standards 5 for protecting the journals from grindings. Also a felt washer or packing 2? cooperates with the guard 21 in protecting one of the journals 6 from grindings which may pass from the endless grinding e1ement M as the latter passes over the pulley I 3.

The pulley 3 being adjustable endwise of the shaft 4 of the electric motor permits aligning of the drive belt at all times regardless with what pulley of the group of pulleys 8 the belt is in engagement with.

If desired, a machine of this kind may be constructed minus the grinding wheel 9, and if so a standard 28 is employed in lieu of the standard 5 and has journaled thereon a shaft 29 carrying a group of belt pulleys 38 protected by a guard 31. The shaft 29 has secured thereto the pulley l3. It is preferable that the pulley l5 be constructed of some yieldable material such as rubber which will present a cushioning effect or give when sharpening a razor, knife or the like so that a smoother grinding will be had on the cutlery during the grinding operation.

The rest m which is especially shaped for supporting blades of scissors or shears for grinding on the grinding wheel 9' has a portion thereof reduced and provided with flattened faces and disposed angularly to its post. The upper edge of the angularly related end is designated by the character iii and is shown as having a bevel thereto so that when a blade of scissors or shears is positioned thereon the cutting edge of said blade will be presented properly to the grinding face of the grinding wheel 9' so-that said cutting edge will be sharpened with a proper bevel. In sharpening the blade of the scissors or shears the handle end is first engaged with the grinding wheel 8' with the grinding operation proceeding toward the free end of the blade. A rest ll! of the character described will prevent the blade of the scLssors or shears from slipping oii of the rest and support the blade at a proper angle to the grinding face of the grinding wheel 9 so that an efficient cutting edge will be ground on said blade.

Referring to the tightener H the upstanding portion of the bracket i8 thereof is provided with a lug it which operates in a slot 20' to aid in preventing the member it from moving out of vertical alignment with the vertical portion of the bracket it but which will permit the member H) to be easily adjusted vertically on the vertical portion of the bracket I8 when the nut on the bolt joining these parts has been backed up.

What is claimed is:

In a grinding device, a standard, a grinding element rotatably mounted on said standard, a table disposed adjacent said standard and formed with spaced arms receiving therebetween said element and adapted to support a work-piece thereon for engagement of the cutting edge of said work-piece-with said element, a support on said table adapted to engage a non-cutting edge of said work-piece, adjustable means connecting said table to said standard to permit vertical and horizontal adjustment of the table with respect to said element, and a member carried by said-table and threadedly connected to said support for adjusting the latter relative to said element whereby said work-piece is moved by said support towards-said element to effect grinding of said work-piece in a direction towards said cutting edge.

ARNOLD R. JOHNSON. 

